An easy one: The sun’s never in the northern sky,
period.
Thus, if your illuminating window faces north,
essentially, the sun’s never there, thus the direc-
tion of the light’s always unaltered.
Elsewise, as referred to, the sun rising in the
east, setting in the west, the sun moves across
the sky there, thus, the angle of the light alters
every few hours.
Try painting anything from a window not any-
where but north, and the angle of the sun’s rays
shift so dramatically, you’ll need cease the work
after a few hrs.
On the other hand, though, from a north-facing
window (“the artist’s window”), that light angle
remain unaltered. All ya then need be concerned
with is the intensity of the light (and that’s Mother
Nature; no window can affect that).
r

Yeah I think it is because your main source of illumination is usually the blue sky.
I always seek shade when painting plein air and I have heard it recommended that it is best to wear a light sky blue shirt because the light hitting you, which is sometimes direct sunlight, will reflect the “correct” color light upon your painting, whereas, for instance, a red shirt may cast a redness upon your painting surface.

The sun’s never in the northern sky, in every
hemisphere, period.

Are you sure ?

Oooh, I guess art and science don’t mix!!

If you live in the northern hemisphere – north of the Tropic of Cancer, and below the Arctic Circle, the sun is always in the southern sky. So, if the light in your studio is entering through north facing windows, there will be no direct sunlight and the light will be more consistent through the day – one reason artists prefer it. I have usually heard it referred to as “north light” rather than “north daylight,” but that’s a minor point. Sometimes artists just say that they prefer north facing windows in their studio.

If you live between the latitudes of the Tropic of Cancer and the Tropic of Capricorn, you sun will appear in both the southern and northern sky depending on the time of year. If you live between the Tropic of Capricorn and the Antarctic Circle (in the southern hemisphere), then the sun will always appear in the northern sky.

So if you live south of the Tropic of Capricorn, you might want the windows in your studio getting south light.

I hope I’m right. Maybe some of our southern hemisphere folks will chime in!

Don

[I]3/13/13, Quote from [B]Charlie:[/B]
if you live in the northern hemisphere, the sun will
pass overhead slightly to the south[/I]
I’m frankly unaware of what the meaning of that
is.
The sun’s never in the northern sky, in every
hemisphere, period.

Don is right.
In Australia the sun is due north at midday and has a altitude of around 57 degrees at this time of the year, so we would want south facing windows in a studio.

It’s interesting the conversation that has developed here. I think most of it is well intentioned and the information submitted is insightful.
I think the most understood idea behind “northern light” is that for most of the daylight hours, a consistent cool light is coming in from a northernly direction; thus the lighting on your subject matter and painting is indirectly from the sun, providing a full spectrum of light, which is very hard to get from artificial means, as mentioned above.
mv-Frank

it is a cool light source that stay truest during the day. you can us west light if painting in the morning east light in the afternoon. or north light all day. south light is the most unstable.